6405709944 has 64 divisors (see below), whose sum is σ = 16922188800. Its totient is φ = 2016533376.

The previous prime is 6405709943. The next prime is 6405709949. The reversal of 6405709944 is 4499075046.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 6405709893 and 6405709902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6405709943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29839 + ... + 117054.

It is an arithmetic number, because the mean of its divisors is an integer number (264409200).

Almost surely, 2^6405709944 is an apocalyptic number.

It is an amenable number.

6405709944 is an abundant number, since it is smaller than the sum of its proper divisors (10516478856).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6405709944 is a wasteful number, since it uses less digits than its factorization.

6405709944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147004 (or 147000 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 48.

The square root of 6405709944 is about 80035.6791937196. The cubic root of 6405709944 is about 1857.1875195774.

The spelling of 6405709944 in words is "six billion, four hundred five million, seven hundred nine thousand, nine hundred forty-four".